Improvement in bolt-heading machines



UNITED STATES PATENT (")EEICEo EDWARD KAYLOR, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN BOLT-HEADING MACHINES.

Specification forming part of Letters Patent NO. 55,501, dated June 12, 1866.

To all 'whom t may concern:

Be it known that I, EDWARD KAYLOR, of the city of Pittsburg, in the county of Allegheny andV State of Pennsylvania, have invented a new and useful Improvement in Bolt- Machines 5 and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, forming part of this specifica-- tion, in which- Figure l is a plan or top view ofmy improved machine, the top lever being removed. Fig. 2 is a vertical longitudinal section through the line :v w of Fig l.

In both gures like letters of reference denote similar parts.

My machine is designed to make what are called square-head bolts 77 that is, bolts with a round or cylindrical shank extending up to the head and a four-sided rectangular head.

rlhe usual mode'of making such bolts is to take a piece of round iron of the diameter of the shank of the bolt and insert it (one end being previously heated to a weldin g heat) between a pair of dies 'having a cylindrical cavity to gripe or hold the iron and an enlarged square cavity in which the head is formed by means of a heading-tool, which staves up the iron into the head-cavity of the dies.

The objection to this mode of making bolts is twofold: First, the head is seldom well shaped, the corners and edges of the head being not sufficiently sharp and well defined, owing to the difficulty of forcing the iron by staving up into the angular corners of a die or matrix; and, second, the staving operation, when performed as described, within a close or incloscd cavity, causing the derangcment and disruption of the fibers of the iron to such an extent as to weaken the neck of the bolt where the shank unites with the head.

Various plans have been tried, with more or less success, to overcome these difliculties, such as striking the head of the bolt with a triphammer while it is surrounded by the sides of the heading.- cavity of the die, and striking Y the sides and corners of the head with dies converging toward the center of the bolt; but

. none of these modes of operation fully accompurpose of obviating the diiculties experienced in making square-head bolts, as above described, operates by squeezing or compressing the head of the bolt on two opposite sides only at one time, and staving up the iron to form the head, by means of a heading-tool, into the space formed by the compressing-dies, thus leaving room for the iron to expand or spread in all directions before it is compressed by the squeezing-dies 011 two sides, the other two sides being entirely unconfmed. The heading-tool and the two squeezing-dies then retire, and another pair of squeezing-dies advance and compress the other two sides ofthe head, this operation being repeated two or three times before the bolt is released from the machine.

In order to enable others skilled in the art to construct and use my improved machine, I will proceed to explain its construction and operation.

In the drawings, a a is the frame of the inachine, having a cross-piece, b, near the rear end, and a horizontal table, c, at the forward end, to support the various parts of the machinery. It has two principal shafts-viz., the driving-shaft d, placed horizontally across the machine near its rear end, and an auxiliary shaft, e, placed lengthwise to one side of the center ofthe frame. The drivin g-shaft d has a beveled cog-wheel, f, which gears into the beveled cog-Wheel f at the rear end of the shaft e.

The cog-wheel fon the driving-shaft lnay be the same size as the cog-wheel j" of the shaft e, or one-half, one-third, or one-fourth of the size of the cog-wheel j", so that the auxiliary shaft e may complete each of its revolutions at the same time that the shaft d completes one of its revolutions, the driving-shaft making one, two, three, or more complete revolutions for each revolution of the auxiliary shaft e, according to the relative size of the gearwheels fand f.

The drivin g-shaft d carries an eccentric cam, g, which works in a cam-yoke, h, which is attached to the stock t' of the heading-tool lf, whereby the heading-tool makes one stroke advancing and receding for each revolution of the shaft d. rThe heading-tool moves horizontally lengthwise of the machine, and is fixed in its stock z' by a set-screw zr, so that the tool may be changed according to the size of bolt to be made.

Attached to the table c are four levers, Z l Z/ Z, two of which, Z Z', have their motion in a horizontal plane, and the other two, Z Z, in a vertical plane. The two horizontal levers are shown in Fig. l and the two vertical levers in Fig. 2. These four levers are similarly shaped, and each is furnished at the extremity of its short arm with a die, (marked, respectively, m m m ml.) These dies are so shaped that when the two horizontal levers Z Z' are operated to advance the dies they present each a plane vertical face, parallel to each other and to the vertical plane passing through the axis of the heading-tool 7c, the space between the face of these two dies m m being equal to the diameter or square of the head of the bolt. ln like manner the two vertical levers Z Z are so situuate and operated that when the short arms arel caused to advance toward each other their dies m and m present their plane faces parallel to each other horizontally, their distance apart at the time vof their nearest approach being equal to the diameter of the head of the bolt. As the four dies m m' m m never meet togetherso as to form a square cavity or matrix, (because one pair is made to recede as the other pair advances.) the width of' the plane face of these dies may be slightly greater than the diameter of the head of the bolt.

The horizontal levers Z Z have their center of motion at 'n a', being supported by the table c; and the vertical levers Zl Z have their center of motion at u u, being supported by the brackets p p', attached to the upper and under sides of the table c, respectively.

Each of the levers Z, Z, and Z has a sprin g, q, bearing upon its short arm, so as to cause it to recede. The lever Zll does not need any spring, owing to its vertical position, the superior weight of its long arm causing it to fall and thereby raise the die m to the position shown in Fig. l.

The four levers Z Z Zll Z are operated by means of wedgeshaped projections on the stock Z of the heading-tool. Of these wedgeshaped projections or cams, two (marked r r, Fig. 2) operate the upper and lower vertical levers, Z and Z, respectively. These cams form inclined planes, as shown in the drawings, on the face of which rests a friction-roller, s, inserted in the rear end of each lever.

Vhen the stock t' of the heading-tool is at the endofitsforward stroke the rollerss srest on the surface of the stock Z,eacl1 at the foot of its inclined cam, and as the stock Zrecedes the cams force the rear extremities of the levers Zl Z farther apart,raising one and depressing the other, until at the termination ofthe backward stroke ofthe stock Z the dies m m' are brought so near together that the distance between their operative faces is exactly equal to the diameter of the head to be formed on the bolt.

The wedge-shaped cams r r', which operate the horizontal levers Z Z', project from the sides of the stock i and incline in the opposite direction to the cams r r. They are also situate a little in the rear of the cams r r, so that when the rollers s s of the levers Zl Z are on top of the cams r rl the rollers s s at the rear end of the levers Z Zl are at the foot of their respective cams r r. The result of this arrangement is, that as the stock t' of the heading-tool advances the rear extremities of the horizontal levers Z Zl are forced apart and the dies m m are closed as the dies m m open, and on the return stroke of the stock z', as the heading-tool recedes, the dies m mf'are closed and the dies m m are opened.

Immediately in front of the compressingdies m m m" m are placed the griping-dies t t, which are situate horizontally across the machine. Each of these dies has a semi-cylindrical cavity, (shown in the die t at u in Fig. 2,) so that when their faces are brought together they form a cylindrical cavity of the diameter of the shank of the bolt. The die tis stationary, but the die t is movable, sliding horizontally to and from the stationary die t. rllhe movable die t has a friction-roller, t, at its outer end, which rests against an eccentric cam, w, fixed to and revolving with the auxiliary shaft c.

By the revolution ofthe cam w the die t is advanced toward the stationary die t, so as to gripe the iron rod fed into the machine to make the bolt, and during the remainder of the revolution of the shaft c the cam w holds the die t firmly up against the die t. So soon as the cam w releases the'` die t a spring, y, forces the die t backward, so as to release the bolt from the griping-dies. As soon as the iron rod is fed into the machine, and is held firmly by the griping-dies t t', the bolt is severed from the iron rod by means of the cutters z z', which are so constructed and arranged as to cut off the bolt at any required length.

The stationary cutter z is attached to or forms part of the plate a', which is placed on the table c of the machine, to which it is fastened by a screw, ZZ', passing through a slot, c', iu the cutter-plate a', so that the critter z may be fixed at any desired distance from the griping-dies t t.

The moving' cutter z', which acts with the cutter z like a pair of shears, turns on or with a rod or shaft, e', and is operated by means of a cam, w', on the auxiliary shaft e, the cam w' being so adjusted as to raise the lever-arm of the cutterzf'once on every revolution of the shaft e immediately after the cam w on the same shaft e has closed the griping-dies t t.

In order to avoid the necessity of adjusting the cam w', in case a lon g-shanked bolt is to be made, the lever-arm z and cam w may be placed outside of the frame ofthe machine on an extension of their shafts e and c, the leverarm z being made to turn the shaft on its axis sufficiently to operate the moving cutter, which may be detached from the lever-arm z and ad justable on the shaft e by means of a set-screw, in which case the shaft e should be square instead of cylindrical. l

The operation of my machine is as follows: The parts of the machine being in the' position shown in Fig. l, the side compressing-dies, m

m', being open, and the griping-dies t t being also open, the iron rod, first properly heated at the end which is to form the head, is inserted through an opening, g', in the end of the frame a. The movable griping-diet advances rapidly and seizes the iron rod in the cavity between it and the die t, while the headingtool 7c commences to advance. The moving cutter z then cuts off the bolt from the rod, and as the heading-tool 7c and its head-stock ad- Vance the side compressing-dies, m m', are closed, and the top and bottom compressingdies, on m", are opened by the operation of the inclined cams before described.

The heading-tool,as it advan ces,staves u p the end ofthe iron between the side compressingdies, m m', which close gradually as the iron is being staved up, and do not reach their point of nearest approach until the staving operation is complete, so that the iron is not staved up into a confined space, but is gradually compressed on two sides during the staving operation, while the other two sides (top and bottom) are free and unconfi ned. By this means the iron is staved without serious disruption of its fibers, which are bent, but not broken. The side dies, mm', then open as the header-stock z'recedes, and simultaneously the top and bottom dies, m m, close, thereby compressing into shape the two sides of the bolt-head which were not previously acted on. If the cog-Wheels f andj" are of the same size, the cam w would now cause the movable griping-die t to open and discharge the bolt; but as a repetition of the operation is desirable, I

lprefer to have these wheels of such relative size that the shaft d will revolve twice, three times, or oftener for each revolution of the cam-shaft e or the same result may be pro-` duced by making the cam g of such shape as to effect two or more complete strokes of the header-stock t for each revolution of its shaft d. In either case the operation of the closing of the side dies, m m', and simultaneous staving of the iron, and the retiring of the headin g-tool and advancing of the top and bottom dies are repeated one or more times, as the case may be before the griping-dies open to deliver the finished bolt.

Having thus described my improved machine for making square-head bolts, what I claim as my invention, and desire to secure by Letters Patent, is-

Forming the head on square-head bolts by means of a machine constructed and operating substantially as hereinbefore described, by staving up the iron with a heading-tool between two side dies, which at the same time advance and compress the iron as and while it is being staved, and then compressing the other two sides of the head by another pair of dies, which advance and compress the opposite sides of the head as the first pair recede, the operation being repeated until the head is properly formed.

In testimony whereof I, the said EDWARD KAYLOR, have hereunto set my hand.

. EDWARD KAYLOR. Witnesses: W. BAKEWELL, A ALLAN C. BAKEWELL. 

